The major objective in this research is to make significant contributions to organic chemistry and medicine through synthetic studies on highly physiologically active complex natural products, including neurotoxins and antibiotics. In 1977-1978, we will study (1) synthesis of saxitoxin and tetrodotoxin analogs for activity-structure relationship study, (2) a total synthesis of histrionicotoxin, (3) a total synthesis of gephyrotoxin, (4) a total synthesis of Beta-lactam antibiotics, and (5) synthesis of a variety of optically active epidithiapiperazinediones for test.